Which of the following is true? (There can be one or more correct answers)
Inorganic compounds can only be analysed in the far-IR region
Mid-IR region is the most widely used IR region for most of the cultural heritage samples
Near-IR region is more used for quantitative analysis than mid-IR region
Polymers typically have characteristic absorption bands in the mid-IR region
Far-IR region is useful for analysis of organic compounds
Which of the following vibrations are diagnostically useful in infrared spectra? (There can be one or more correct answers)
C-H stretch
C-C stretch
C=O stretch
C-O stretch
Spectrum presented in the absorbance scale can easily be converted into spectrum presented in the transmittance scale and vice versa
Spectrum presented in the transmittance scale can easily be converted into spectrum presented in the absorbance scale, but vice versa is not possible
The spectra recorded in the transmittance and absorbance scales enable seeing different structural features of the same sample
Different type of equipment is needed for recording absorbance and transmittance spectra
In IR spectrometers signal-to-noise ratio is an issue because … (There can be one or more correct answers)
… IR sources typically have low intensity
… IR detectors typically have low sensitivity
… oxygen from air strongly absorbs IR photons
… IR radiation cannot be efficiently reflected
… IR radiation cannot be efficiently focused
Which of the following compounds/ materials do not give useful IR spectra? (There can be one or more correct answers)
Inorganic compounds
Homonuclear molecules (O2, N2, Cl2)
Organic compounds
Minerals
Polymers
Carbon
In which IR spectral region oxides and sulphides have characteristic vibrations? (There can be one or more correct answers)
Far-infrared
Near-infrared
Mid-infrared
What would happen if FT-IR didn’t use Fourier Transform? (There can be one or more correct answers)
We’d see an uninterpretable spectrum
We’d get less accurate spectra
The spectra would have inferior signal-to-noise ratio
There are three most commonly used ATR materials - diamond, zinc selenide and germanium. Which of the following statements applies to which crystal?
Unselect
What is the following formula used for in practice?
To estimate the depth of penetration in ATR-FT-IR spectroscopy
To calculate ATR crystal's refractive index
To estimate the critical angle of internal reflection
Calculate the wavelength in nm, if the wavenumber is 3000 cm-1.
Please write just the nominal value without unit
Which of the following statements is true? (There can be one or several correct answers) ATR is …
a reflection technique
a sampling technique that requires a smooth surface
a non-contact technique
a sampling technique that can be used for the analysis of tiny samples
a technique in which quartz is used as crystal material
What are the advantages of FT-IR microspectroscopy compared to the conventional FT-IR spectroscopy? (There can be one or more correct answers)
Enables analysis of small parts of the large samples
Enables analysis in the far-IR region
IR mapping possibility
Enables determining the homogeneity of the sample
DRIFTS is a commonly used as sampling technique in FT-IR microspectroscopy
The smallest sample size can be a few mm in diameter
Which materials ATR-FT-IR spectrum this is? Please compare the IR spectrum with reference spectra available at https://spectra.chem.ut.ee/.
Beeswax
Linseed oil
Gum Arabicum
Egg yolk
Colophony
Polyvinyl acetate
Which answers are correct? FT-IR enables easily distinguish between… (There can be one or more correct answers)
… different types of oils
… different fillers in paper
… different types of varnish
… different types of proteins (e.g. animal glue, wool, egg white)
… oil and egg tempera binder
… oil and resin
… fresh and dried oil
… different types of ochres
… chalk and quartz
… cotton and linen textile fibres
